---In SergentEng@..., <fsergent@...> wrote :
As some have noticed, our EC87A's are indeed assembled by expanding the pin on the bottom cover. There is also a glue dot added underneath the coupler after assembly to ensure the cover doesn't split away from the top casting under heavy load.
If you try this at home, use very little pressure. The operation here is done in a specially designed pneumatic press that first seats the cover tightly against the top casting and then applies a controlled pressure to a steel pin that expands the "rivet". The application of pressure is actually very slow compared to the snap of an automatic center punch or the whack of at hammer. That is not to say that you can't successfully do the operation with a hammer or and automatic center punch. With a little practice that results in a small pile of defective couplers for "scenery items", you can probably figure out how to do the operation reliably. I still recommend glue on the bottom of the coupler thumb to prevent separation under load.
I'm very confused after reading this post. To me it seems that the glue is being applied on the bottom part of the coupler thumb;how is this holding the bottom part of the coupler in place putting glue on the thumb where there appears to be no seem? I'm sure I'm missing something here but not sure exactly what. I understand about the pressure to the pin to spread it out before assembly so when assembled it can't break away.